Mikkel Kessler will put his boxing career on the line against Carl Froch, vowing to walk away from boxing should he lose the super-middleweight unification bout "fair and square".

WBA champion Kessler won his first encounter with Froch in Denmark in April 2010, a result that the IBF champion is desperate to put right at The O2 on May 25.

And while the pair's friendship away from the ring has curbed the trash talking, Kessler's declaration has added extra spice to what was already shaping up to be the biggest fight on British soil in 2013.

"If I lose, I'm going to quit," Kessler told Sky Sports News. "If I lose fair and square, I'm out of here, sorry. But I'm not going to lose, I'm going to win."

Kessler's trainer Jimmy Montoya has invited George Groves to Copenhagen to spar with the Dane in the build-up to the fight in the hope of learning something from the Commonwealth champion's sparring sessions with Nottingham native Froch.

But whether or not the Londoner, who will appear on the undercard on fight night, heads to Denmark, Kessler is confident that his preparations are on track.

"We have a good plan," Kessler added. "I think he's going to come with hair on his chest when he's fighting me and show everybody he's the champ. He's probably going to come running forward at me in the first couple of rounds, but let's see what's going to happen."